In the present invention, it is possible to prevent displacement of a wing-shaped flap while being worn and to stably fix the wing-shaped flap to underwear even when the area of a wing-displacement-preventing adhesive layer is decreased, the wing-displacement-preventing adhesive layer being provided to the wing-shaped flap. The area of the wing displacement-preventing adhesive layer (16) is 5 to 20% of the area of the wing-shaped flap (W). The wing-shaped flap (W) forms an asymmetric shape at the front side and rear side of a widthwise line passing through an outward end section (Wa). The wing-shaped flap (W) has an overlaying section (22), in which the front end sections of the wing-shaped flap (W) overlay each other in a state in which the wing-shaped flap (W) is folded so as to wrap around a crotch portion of the underwear while being worn. The wing displacement-preventing adhesive layer (16) is provided in a range surrounded by a widthwise line (S1) passing through the front end section of the overlaying section (22) and a widthwise line (S2) passing through the rear end section of the overlaying section (22). The outline of the wing-shaped flap is formed so as to have a substantially arcuate shape at least in the overlaying section (22).
